But Dungan’s technique can infer ancient protein sequences even without this information. For that matter, they can’t even say precisely what species they are. Scientists haven’t yet recovered genetic material from the fossils for these two extinct species.
They focused on common ancestors of Cetacea and Whippomorpha (the group of animals that includes cetaceans and hippos), representing a time period of about 55 to 35 million years ago. In the study, the researchers compared rhodopsin, the visual pigment responsible for dim-light vision, in the animals that bookended the land-to-ocean transition. But studying extinct cetaceans is especially interesting because the land-to-ocean transition transformed the animals’ visual realms. They’ve applied the technique across the animal kingdom, learning more about how extinct species saw the world. In 2003, researchers at U of T pioneered a technique to recreate extinct animals’ ancient visual proteins. “The paper is the end of a story that started when I was really young.” Learning about the evolutionary transition that modern whales took-from ocean to land and back again-“totally blew me away,” she says. The notion that an animal could transform from living entirely out of water to not being able to live outside of it stuck with her. Her dad told her in passing that the ancestors of modern whales once lived on land. As a kid, she loved spending time in the water and learning about marine biology. It’s given Dungan and her colleagues a new look into how proto-cetaceans would have lived in the immediate aftermath of a crucial evolutionary juncture: the time roughly 55 to 35 million years ago when the animals that eventually became whales and dolphins abandoned their terrestrial lifestyles to return to the sea.ĭungan’s fascination with whale evolution began when she was 8. In the most recent example of this technique in action, scientists led by Sarah Dungan, who completed the work as a graduate student at the University of Toronto (U of T) in Ontario, have revived the visual pigments from some of cetaceans’ earliest ancestors.
This molecular necromancy can help them understand traits that don’t preserve in the fossil record. But a developing technique is giving researchers a physiological cipher to decrypt the behavior of extinct species by reconstructing and analyzing extinct animals’ proteins. It’s nearly impossible to know how extinct animals behaved there’s no Jurassic Park where we can watch them hunt or mate or evade predators. This article was originally published by Hakai Magazine.